| The yield of potato residue is very large every year in China, because of a lack of way for potato residue comprehensive large amount of potato residue are traditionally burnt in the field and causing pollution of the environment. This study aims to make potato residue modified by chemical method to be paper wet end chemical additive to realize high added value transformation. The main content of potato residue are short fiber and starch granule, the starch and cellulose could be well used for chemical modification after pretreated by appropriate ways and finally applied as retention & filter aids. Then we might to get the best using way of modified potato residue additives. Exploring the optimal retention and drainage system compose of it. At last, modified laser sizers which based on fluorescent counting method used to detect retention effect of the modified potato residue additives. The result showed that it can be used to accurately measure the size and concentration of fines partieles in the white water after filter.Through SEM analysis, potato residue was mainly comprised of cellulose and starch with different size, and the starch was packaged by reticular fibre. After the fiber coarse grinding and ball-mill micronization pretreatment, the fiber size was close to starch and the potato residue can realize homogenization. With ion chromatograph of potato residue analysis, four kinds of monosaccharides were detected and respectively with content of 85.63% glucose, 1.82% arabinose, 1.28% galactose, 2.85% xylose. The relative crystallinity of potato residue decreased after homogenization. The pretreated potato residue could be used for chemical modification with good reaction uniformity and nice accessibility for chemical reagent after series of pretreatment.Oxidization and cationization proceeded one by one to modify the potato residue. The optimization parameters of oxidization modified was describe as follow: the dosage of H2O2 was about 6%,reaction temperature was about 45℃, the dosage of Catalyst was 0.12%, pH value was about 4.0, reaction time was 45 min. The optimization condition of oxidization modified as follow: concentration of substrate about 10%, mCHPTMA:mOPR=0.4~0.5:1, mNaOH:mCHPTMA=2.0, reaction time was about 3h, reaction temperature was 50℃. Then through the SEM, FT-IR, 13C-NMR and TG analysis technical which was used to study on chemical structure and thermal stability properties characterization of potato residue modified products, and all of these analysises had proved the product were synthesised successfully.The best adding contition of product for retention and drainage were optimized as follow: the dosage was about 1.2%, the speed of dynamic drainage jar was 750 rpm per minute, pH value was from 7 to 9, the optimum contact time of the product with stock was 10 ~ 20 s, less affected by conductivity. The appearance of product is light yellow solid which is bibulous become wet easily. The product shows very excellent retention and drainage performance in deinking pulp added to the stock without any fillers and additives consistent with the actual plant conditions.Modified laser sizers based on fluorescent counting method which was developed in our laboratory was used to detect retention effection of retention aids. The research result showed that the modified laser sizers can accurately measure the size and concentration of fine particles in white water after filter. The main size of fines partieles ranged 0.35~16μm. There was a obvious depletion in numbers of fine particles and the size of them increased. |
